Oregon State quarterback Luke Del Rio (12) warms up before an NCAA college football game on Sept. 6, 2014, in Honolulu. (Eugene Tanner, The Associated Press)

During a phone interview with Oregon State senior quarterback Sean Mannion this week, I asked him how former Valor Christian star Luke Del Rio is progressing.

Del Rio, son of Broncos’ defensive coordinator Jack Del Rio, was a walk-on redshirt at Alabama for a season before transferring to Oregon State. As the top backup to Mannion, Del Rio (6-foot-1, 208 pounds) has played in one game this season and does not yet have completion. Del Rio is a redshirt freshman in eligibility.

Oregon State plays Saturday (2 p.m., Pac-12 Network) at Colorado.

“Luke is doing great,” Mannion told me. “We’re roommates and he’s a friend of mine. He’s obviously backing me up at quarterback, and he’s great to work with on a daily basis.

“He knows a lot about the game. It’s great to have a guy like him, and our other quarterbacks, to bounce (ideas) off of in the meeting room and during a game.”

I asked Mannion what Del Rio needed to work on.

“The biggest challenge for a quarterback at this level is getting a hold of the offense,” Mannion said. “From there, the game really slows down. When you know what you’re doing out there and what your receivers are doing, then you can really think about the defense and just worry about what they’re doing to defend your plays.

“As Luke continues to know our offense better and better, the game will slow down for him. He already has a good grasp of the offense. Once he gets more reps, the better he will be.”

Terry Frei graduated from Wheat Ridge High School in the Denver area and has degrees in history and journalism from the University of Colorado-Boulder. He worked for the Rocky Mountain News while attending CU and joined the Post staff after graduation. He has also worked at the Oregonian in Portland, Ore., and The Sporting News. His seventh book, March 1939: Before the Madness, was issued in February 2014.